Naeser M A, Gebhardt C, Levine H L
Arch Neurol. 1980 Jul;37(7):401-9. doi: 10.1001/archneur.1980.00500560031002.
Patients in their 50s who show clinical signs of dementia (possible Alzheimer's disease) often have ocmputerized tomographic (CT) scans that appear normal. This study examined the mean CT number within a 169-pixel sample in white matter in the centrum semiovale slice. Slice sizes ranged from 6,800 to 9,000 pixels; all were without contrast enhancement. The CT numbers were higher for six nondementia cases (CT numbers of 41 and above)than for 14 dementia cases (CT numbers of 40 and below). The non-overlap in mean CT numbers between the two groups was observed independent of the presence or absence of prominent sulci. Similar low CT numbers were observed for seven patients with senile dementia. Differential diagnosis between dementia and depression may be better aided by studying the CT numbers rather than the presence of prominent sulci.
50多岁出现痴呆临床症状（可能为阿尔茨海默病）的患者，其计算机断层扫描（CT）结果常显示正常。本研究检测了半卵圆中心层面白质中169像素样本内的平均CT值。切片大小在6800至9000像素之间；均未进行增强扫描。6例非痴呆病例的CT值（41及以上）高于14例痴呆病例（40及以下）。两组平均CT值无重叠，且与脑沟是否明显无关。7例老年痴呆患者的CT值也较低。研究CT值而非脑沟是否明显，可能更有助于痴呆与抑郁症的鉴别诊断。
